When to Plant Hardy Asters in Zone 3a

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant hardy asters in Zone 3a can be determined by reviewing the USDA zone info.


Planting Calendar for Hardy Asters

Frost tolerance for hardy asters: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Hardy Asters are barely cold tolerant which tells us that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant hardy asters
Possibly ok, but a risky time to plant hardy asters
Probably not a good time to plant hardy asters

The earliest that you can plant hardy asters in Zone 3a is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant hardy asters and expect a good harvest is probably August. Any later than that and your hardy asters may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your hardy asters indoors.

Last Frost Date

The average date of last frost is May 15 in Zone 3a. You can expect an average low temperature of -40°F in the coldest months of winter.

Since the USDA zone info for Zone 3a is an average the actual date of last frost will vary from year to year. Half of the time in Zone 3a you get surprised by a frost after May 15 so make sure that you are ready to cover your hardy asters if you have a surprise late frost.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-40°F
Highest Expected Low-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in your other planting guides for Zone 3a.